Harry Watt, best known for his work on Night Mail (1936) and North Sea (1938), the most commercially successful of all GPO films, deftly combines commentary and visual image (including some library footage) to achieve this clear elucidation of the complex system of General Post Office finance.

The film opens with a member of the British public carrying out an important transaction with the State - the purchase of a ha'penny stamp by a small boy at a local post office. It proceeds as a comprehensive survey of the machinery of post office finance and the relationship of post office finances to the finances of the nation as a whole. From small boys and ha'pennies we are launched into a world of big sums, big institutions and big responsibilities. The commentary informs that the Post Office makes an annual profit of £11million - 'that is eleven million pounds less to be found by means of taxation'. The films is packed with facts like these designed to bolster the Post Office's image as a cherished national institution.

An average day's takings of more than a quarter of a million pounds pass through the Post Office's account at the Bank of England. And responsible for every penny handled is the Accountant General and the team of 2,000 staff working under him, we are told. What we see is a world populated by male bureaucrats in pinstripes poring over account books and row upon row of female telephonists, which betrays the contemporary rigidity in attitudes towards gender roles in the civil service. The world depicted is bureaucracy of the highest order; a world of scrupulously controlled expenditure and revenue. The suits are sharp and the language is curt but there is still room for a light-hearted quip by a senior civil servant about the regrettable new tax on tea.

Mail delivery was the sole function of the Post Office until it started introducing financial services in the nineteenth century, such as the savings bank in 1861. Throughout the twentieth century the Post Office grew from a governmental revenue department, as depicted here, to a fully recognised public corporation with full executive authority in 1969.

Big Money was well received on its release and certainly did no harm to the image of the civil servant.